Cleaning appliance

ABSTRACT

A cleaning appliance vacuum cleaner includes a main body having a rear portion and a roller structure such as side wheels arranged to allow the main body to travel across a floor surface. In normal use, the rear portion is spaced from the floor surface. The rear portion carries a wheel arranged so that, if the main body is tilted so that the rear portion is brought towards the floor, the wheel contacts the floor surface. Thus, the cleaner may be used in a tipped-back position without causing damage to the floor surface as the cleaner is dragged along by the user by a hose attached to the main body. The size and position of the wheel is determined so that, when the cleaner is tipped back, the center of gravity of the main body acts to return the main body to an upright position.

This invention relates to a cleaning appliance, such as a vacuumcleaner.

The majority of vacuum cleaners are either of the ‘upright’ type or ofthe ‘cylinder’ type. Cylinder appliances are called canister or barrelmachines in some countries. An example of a cylinder vacuum cleanermanufactured by Dyson Limited is shown in FIG. 1, and is indicatedgenerally by the reference numeral 1.

A typical cylinder vacuum cleaner 1 comprises a main body 2 containingseparating apparatus 3, such as a cyclonic separator or a bag forseparating dirt and dust from an incoming dirty airflow. The dirtyairflow is introduced to the main body 2 via a suction hose 4 and a wandassembly 5, which is connected to the main body 2. A cleaning tool 6 isattached to the remote end of the hose and wand assembly 4,5. The mainbody 2 of the cleaner 1 is dragged along by the hose 4 as a user movesaround a room.

A problem that may be encountered with conventional vacuum cleaners isthat, in certain circumstances, the main body of the vacuum cleaner maybecome upset from the normal upright position shown in FIG. 1. Forexample, if the user pulls upwardly on the hose when the cleaner is inuse, the main body of the cleaner may tilt backwards, bringing the rearportion of the main body towards a floor surface. If the user continuesto drag the cleaner along by the hose in this tipped-back position,damage may occur to the floor surface due to the rear portion bearingagainst, and being dragged along, the floor. Furthermore, use of thecleaner in the tipped-back position may be detrimental to theperformance of the appliance.

The invention provides a cleaning appliance comprising a main bodyhaving a rear portion and means arranged to allow the main body totravel across a floor surface, the rear portion being spaced from thefloor surface in normal use and having a wheel arranged so that, if themain body is tilted so that the rear portion is brought towards thefloor surface, the wheel contacts the floor surface.

The provision of a wheel on the rear portion permits the cleaner to bepulled across a floor surface when the main body is in the tipped-backposition, whilst preventing the rear portion from scraping against thefloor. Thus, damage to the floor surface is prevented.

Advantageously, the wheel is arranged on the rear portion so that, inthe tipped-back position, the centre of gravity of the main body acts toreturn the main body to its normal upright position. This may beeffected by selection of the size, position and projection of the wheel.This feature ensures that the main body does not remain in a positionthat may cause the performance of the separating apparatus to beadversely affected.

Use of the term “wheel” is intended to encompass rollers and rollingsurfaces in general.

The wheel may be incorporated in a housing that is fixed with respect tothe main body of the cleaner. Alternatively, the wheel may be permittedto swivel with respect to the main body.

Although the invention is described in detail below with reference to avacuum cleaner, it will be appreciated that the invention can also beapplied to other forms of cleaning appliance. The term “cleaningappliance” is intended to have a broad meaning, and includes a widerange of machines having a main body and a hose for carrying fluid to orfrom a floor surface. It includes, inter alia, machines which only applysuction to the surface, such as vacuum cleaners (dry, wet and wet/dryvariants), so as to draw material from the surface, as well as machineswhich apply material to the surface, such as polishing/waxing machines,pressure washing machines and shampooing machines.

The invention will now be described, by way of example, with referenceto the accompanying drawings, in which:

FIG. 1 shows a conventional vacuum cleaner of the cylinder type;

FIG. 2 is a side view of a vacuum cleaner in accordance with anembodiment of the invention, with the hose omitted for clarity;

FIG. 3 is a rear view of the vacuum cleaner of FIG. 2; and

FIG. 4 is a side view of the cleaner of FIGS. 2 and 3 in a tipped-backposition.

Like reference numerals refer to like parts throughout thespecification.

With reference to FIGS. 2 and 3, a cleaning appliance constructedaccording to the invention is shown in the form of a vacuum cleaner 7.The vacuum cleaner 7 has a main body 8, which supports the maincomponents of the vacuum cleaner. In a traditional manner, the main body8 has a chassis 9 which supports separating and collecting apparatus 10and a motor-driven fan (not shown) for generating suction which drawsdirt-laden air into the separating apparatus. The main body 8 also hasmeans for allowing the cleaner 7 to be moved across a floor surface 11.In this embodiment two side wheels 12, one on each side of the chassis9, are provided. A further wheel in the form of a castor wheel 13 isprovided, located beneath the front portion of the chassis 9. The sidewheels 12, and castor wheel 13 could be supplemented, or replaced, byother means for allowing the main body 8 to be moved across a surface,such as skids or rollers.

The separating apparatus 10 as a whole is removably mounted on thechassis 9 for emptying and for access to other components locatedbeneath the separating apparatus.

The form of the separating apparatus 10 is not important to theinvention. Whilst it is preferred to use cyclonic separators which spindirt, dust and debris from the airflow, other forms of separator can beused. Examples of suitable separator technology include an inertialseparator, a filter bag, a porous container, an electrostatic separatoror a liquid-based separator.

A flexible hose (not shown for clarity) is connectable to an inlet port14 on the main body 8. Ducting forming part of the chassis 9 connectsthe air inlet port 14 to an inlet of the separating apparatus 10. Theinlet to the cyclonic separating apparatus 10 is arranged to guide anincoming airflow through an opening in the wall of the cyclonicseparator in a tangential manner. The precise details of the ducting andthe cyclonic separator 10 are immaterial to this invention.

The other end of the flexible hose is connectable to a wand, such as thewand 5 shown in FIG. 1. The distal end of the wand 5 is adapted toadapted to receive a floor tool, such as the floor tool 6 shown in FIG.1, in any known manner.

A single continuous hose-receiving channel 15 is provided along thesides and back of the periphery of the chassis 9. The hose-receivingchannel 15 defines part of a storage path for the hose and serves toguide and support the hose when it is stored. Channel 15 has asemicircular shape along most of its length and a diameter that is justgreater than the hose that it retains.

During use, the main body 8 of the cleaner is pulled along the floorsurface 11 by the hose as a user moves around a room. The hose has aconstruction which is robust enough to withstand this pulling action andany normal abrasion, which may be encountered as the hose rubs againstobstacles in a room.

In this embodiment, the air inlet port 14 is centrally mounted on themain body 8 at the forward, lower part of the machine. In alternativeembodiments of the machine where the air inlet is not centrallypositioned, such is the machine shown in FIG. 1 where the inlet is nearthe upper part of the separating apparatus 3, it is preferable to anchorthe hose 4 to the machine at a central position (as with anchor point 16in the machine shown in FIG. 1) so that when a user pulls the hose, themain body 2 follows the user.

The main body has a rear portion 17, which, in normal usage of thevacuum cleaner, is spaced from the floor surface 11 to be cleaned. Therear portion 17 has a surface 18 that is generally transverse to theplane of the floor surface 11. In this embodiment, the rear portion 17includes part of the hose-receiving channel 15 and a storage area 19 fortools 20, 21, 22, which are connectable to the distal end of the hose orthe wand.

In certain circumstances, the vacuum cleaner 7 may become upset from theupright position shown in FIGS. 2 and 3. For example, if the userimparts an excessive upward force to the front of the vacuum cleaner 7by pulling upwardly on the hose, this may have the effect of lifting thefront end of the cleaner. This may be sufficient to cause a turningmoment to be applied to the main body 8. Thus, the main body 8 may tiltbackwards, bringing the rear portion 17 towards the floor surface 11.The user may choose to continue to use the cleaner 7 in this tipped-backposition and pull it along the floor. The cleaner 7 travels across thefloor by means of the side wheels 12 that remain operable in this tiltedposition. This may result in damage to the floor surface 11, or parts ofthe cleaner itself, particularly those carried by the rear portion 17 ofthe main body. Furthermore, operation of the separating apparatus 10 inthis position may be detrimental to its performance.

In accordance with the invention, the rear portion 17 of the main body 8carries a wheel 23. Thus, if the main body 8 is tipped backwards fromthe upright position, to the extent that the rear portion 17 is broughttowards the floor 11, the wheel 23 contacts the floor, as illustrated inFIG. 4. This rear wheel 23 permits the user to continue to pull thecleaner 7 along in the tipped-back position without causing damage tothe surface 11 of the floor. The cleaner 7 travels across the floorsurface 11 by means of the rear wheel 23 and the side wheels 12.

The size, position and projection of the wheel 23 are selected so that,in the tipped-back position, the wheel projects beyond any otherrearwardly-projecting parts of the main body 8. As can be seen in FIG.4, the hose-receiving channel 15 and tool storage area 19 do not bearagainst the floor surface 11 when the cleaner is in the tipped-backposition.

The wheel 23 also provides protection for parts of the cleaner when instorage. For example, the position of the hose when stored on thecleaner is indicated by the broken lines 25. The provision of the wheel23 on the rear surface 18 ensures that the hose is spaced from a floorsurface if the main body 8 is tilted when the cleaner is not being used.This prevents the hose from being damaged by the weight of the cleaner 7bearing down upon it.

The size, position and projection of the wheel 23 are also arranged sothat, when the cleaner is tilted backwards, the centre of gravity of themain body 8 does not act outside the base of the main body. In theembodiment illustrated in FIG. 4, the base of the main body 8 is definedby the side wheels 12. Thus, if the user ceases to pull upwards on thehose, thereby ceasing to apply an external turning moment to the mainbody 8, the main body will tend to right itself and return to theposition shown in FIG. 2.

In this embodiment, the rear wheel 23 has a housing 25 that is fixedwith respect to the rear portion 17 so that the rotational axis of therear wheel is substantially parallel to that of the side wheels 12.Other arrangements may be possible, such as a castor wheel capable ofswivelling motion.

The rear wheel 23 need not be associated with a housing 24, but couldinstead be located on an axle that forms an integral part of the surface18 of the rear portion 19 of the appliance.

The rear wheel 23 may be retractable for storage of the cleaner, forexample. Naturally, a plurality of wheels or other rolling surfaces maybe provided.

The invention has been described with reference to a cyclonic cylindervacuum cleaner, but may be applied to other forms of vacuum cleaner andother cleaning appliances.

1. A cleaning appliance, comprising: a main body having front and rearportions and a predetermined center of gravity, a hose being releasablyattached to the front portion of the main body, and a roller structurearranged to allow the main body to travel across a floor surface, therear portion being spaced from the floor surface in normal use andhaving a wheel arranged so that, in use, if a user pulls on the hose soas to tilt the main body and bring the rear portion towards the floorsurface, the wheel of the rear portion contacts the floor surface, thesize and arrangement of the wheel relative to the main body being suchthat, when the user ceases to pull on the hose, the center of gravity ofthe main body acts to return the main body to its normal position withthe rear portion spaced from the floor surface.
 2. An appliance asclaimed in claim 1, in which the wheel comprises a castor.
 3. Anappliance as claimed in claim 1 or 2, in which the wheel has an axlethat is fixed with respect to the main body.
 4. An appliance as claimedin claim 1 or 2, in which the roller structure comprises at least onewheel or roller.
 5. An appliance as claimed in claim 1 or 2, in whichthe roller structure is arranged to contact the floor surface when themain body is tilted.
 6. An appliance as claimed in claim 1 or 2, furthercomprising a guide located on the main body for guiding the hose along ahose storage path, which path includes the rear portion of theappliance, and the wheel being arranged so that, when the hose is storedalong the storage path and the main body is tilted so that the wheelcontacts the floor surface, the hose is spaced from the floor surface.7-8. (canceled)
 9. A vacuum cleaner as claimed in claim 10 furthercomprising a cyclonic separating apparatus.
 10. A cylinder type vacuumcleaner, comprising: a main body having front and rear portions and apredetermined center of gravity, a hose releasably attached to the frontportion of the main body, and a roller structure arranged to allow themain body to travel across a floor surface, the rear portion beingspaced from the floor surface in normal use and having a wheel arrangedso that, in use, if a user pulls on the hose so as to tilt the main bodyand bring the rear portion towards the floor surface, the wheel of therear portion contacts the floor surface, the size and arrangement of thewheel relative to the main body being such that, when the user ceases topull on the hose, the center of gravity of the main body acts to returnthe main body to its normal position with the rear portion spaced fromthe floor surface.
 11. An appliance as claimed in claim 3, in which theroller structure comprises at least one wheel or roller.
 12. Anappliance as claimed in claim 3, in which the roller structure isarranged to contact the floor surface when the main body is tilted. 13.An appliance as claimed in claim 3, further comprising a guide locatedon the main body for guiding the hose along a hose storage path, whichpath includes the rear portion of the appliance, and the wheel beingarranged so that, when the hose is stored along the storage path and themain body is tilted so that the wheel contacts the floor surface, thehose is spaced from the floor surface
 14. A vacuum cleaner as claimed inclaim 9 or 10, further comprising a guide located on the main body forguiding the hose along a hose storage path, which path includes the rearportion of the appliance, and the wheel being arranged so that, when thehose is stored along the storage path and the main body is tilted sothat the wheel contacts the floor surface, the hose is spaced from thefloor surface.